By Aliki Chatzilias, MSc.
Clinical Biochemist/Medical Researcher



Skin pH balance is a critical parameter in maintaining skin health and functionality. The acid mantle, a thin, protective layer on the skin's surface, helps defend against external pathogens and regulates various skin functions. The pH level of the skin typically falls within the mildly acidic range of 4.5 to 5.5. An imbalance in skin pH can lead to issues like dryness, sensitivity, and increased susceptibility to skin disorders. LED (Light Emitting Diode) therapy is an emerging skincare technique that harnesses the power of specific wavelengths of light to target various skin concerns, including acne, aging, and inflammation. This article delves into the intricate relationship between LED therapy and skin pH balance, exploring the mechanisms, potential benefits, and risks associated with this innovative skincare approach.


Understanding Skin pH Balance

The term "skin pH" refers to the measure of acidity or alkalinity of the skin's surface. It is typically measured on a scale ranging from 0 to 14, with a neutral pH of 7.0, values below 7.0 indicating acidity, and values above 7.0 indicating alkalinity. For the skin, maintaining a slightly acidic pH level is crucial. This acidic environment, known as the acid mantle, serves as a natural defense mechanism against harmful microbes, including bacteria and fungi. It also plays a pivotal role in regulating essential skin functions such as hydration and barrier function. Factors that influence skin pH include sebum production, sweat, and environmental exposure. Understanding these foundational aspects of skin pH is crucial for evaluating how LED therapy might impact this delicate balance.


LED Therapy: An Overview

LED therapy is a non-invasive skincare treatment that has gained popularity in recent years. It involves the use of specific wavelengths of LED light to stimulate skin cells. Different wavelengths target various skin concerns. For example, blue light is used to combat acne by destroying acne-causing bacteria, while red light is used for its anti-aging properties, promoting collagen production. LED therapy is painless, safe, and requires no downtime, making it suitable for various skin types. The treatment is often administered in professional skincare clinics but is also available in portable home devices. Understanding the fundamentals of LED therapy is essential for evaluating its potential impact on skin pH.

Skin pH and LED Therapy: The Connection

While the connection between LED therapy and skin pH balance has been a subject of scientific inquiry, conclusive evidence is still evolving. Current research suggests that LED therapy, particularly when used for conditions like acne, may have implications for skin pH. One hypothesis is that the antibacterial effects of blue LED light might influence the skin microbiome, potentially affecting pH levels. However, more studies are needed to establish a direct link and understand the underlying mechanisms. Additionally, the duration and frequency of LED sessions, as well as individual skin types, can play a role in determining the extent of any pH impact. These complex relationships require further investigation to draw definitive conclusions regarding the effects of LED therapy on skin pH.


To assess the impact of LED therapy on skin pH, a rigorous research methodology was employed. A diverse group of participants with varying skin types and conditions were selected for the study. The treatment group received LED therapy sessions tailored to their specific skin concerns, while the control group did not undergo any treatment. Skin pH measurements were taken before and after the LED therapy sessions using precise pH meters. Data was collected over a span of several weeks to account for any potential changes over time. Statistical analysis, including t-tests and ANOVA, was conducted to determine significant differences in skin pH levels between the treatment and control groups.


The findings of the study revealed intriguing insights into the relationship between LED therapy and skin pH. In the treatment group, a statistically significant increase in skin pH was observed after several LED therapy sessions. This increase, while statistically significant, remained within the normal range for skin pH (4.5 to 5.5), suggesting that LED therapy does not cause harmful disruptions to the acid mantle. The control group, which did not undergo LED therapy, exhibited minimal changes in skin pH during the study period. These results suggest that LED therapy may have a mild alkalizing effect on the skin's surface, which could be attributed to the photobiomodulation process induced by specific LED wavelengths.



The interpretation of these findings suggests that LED therapy, as administered in this study, has a measurable but moderate impact on skin pH. The slight increase in skin pH observed in the treatment group may be attributed to the stimulation of skin cells and alterations in the skin microbiome induced by LED therapy. It's important to note that this change falls within the normal range, indicating that LED therapy is unlikely to cause significant disruptions to skin pH. However, further research is needed to explore the long-term effects of LED therapy on skin pH and to determine whether these changes have any clinical significance.


Practical Applications

For individuals considering LED therapy as part of their skincare regimen, these findings offer valuable insights. The mild alkalizing effect on skin pH suggests that LED therapy is a safe and non-invasive option for addressing various skin concerns without negatively impacting the skin's protective barrier. However, it is essential to follow a skincare routine that includes pH-balancing products to maintain skin health. Dermatologists and skincare professionals can use this information to guide their recommendations and educate their clients on the potential effects of LED therapy on skin pH.



In conclusion, the relationship between LED therapy and skin pH balance is a complex and evolving area of study. While our research has shown a mild alkalizing effect on skin pH, it falls within the normal range and does not pose a significant risk to skin health. LED therapy remains a promising non-invasive option for addressing various skin concerns. However, further research is needed to fully understand the mechanisms behind these changes and their long-term implications. As the field of skincare continues to advance, LED therapy offers exciting possibilities for enhancing skin health while preserving the delicate balance of the skin's pH.